1. Field of the Invention
This invention relates to a unique communication system that allows multiple mobile and stationary computers to communicate information, and more specifically oil and gas field information with a remote supervisory control and data acquisition (SCADA) system in a wireless multicast network environment. More specifically it relates to an improved oil and gas field data communication methodology that affects improved oil and gas field operating efficiency.
2. Background of the Related Art
The majority of oil and gas fields cover a large geographic area and are often situated in remote and adverse terrain. Because of the communications protocol typically used and the limited historical memory of the SCADA system, the master computer system has to constantly scan the field. The constant scanning of remote SCADA units inherently ties up the radio system and disallows any other computer systems from scanning the SCADA units. The conventional (SCADA) supervisory control and data acquisition system uses the spread spectrum or licensed frequency data radio for a single host or for a single master system to scan the remote telemetry units (RTUs) or slave systems in the field to, for example, to retrieve measurement data from a remote telemetry unit and or to download a command from a master control unit to activate an element, i.e., to turn a valve off or on. For other computer systems to access field or RTU remote telemetry unit data, it must go through the master computer host outside of the radio network. This in turn requires a second computer networking system and software to allow another computer within the network to access the field or RTU's remote telemetry unit data. In the known prior art, U.S. Patent Publication 2003/0162538 appears to teach remote control units and a telemetry data reporting system that allows remote control from a remote communication center which sends out and receives transmissions. U.S. Pat. Nos. 5,941,305 and 6,041,856 appear to teach a real-time data acquisition system using remote control units that report data variables such as temperature, pressure, flow characteristics etc. via radio link. U.S. Pat. Nos. 4,721,158; 5,252,031; and, 5,819,849 appear to teach oil well pump control systems through monitoring by RTU's. U.S. Patents and Publications 2003/0174070; 200210198978; U.S. Pat. Nos. 3,803,362; 5,335,730; and, 5,010,333 appear to teach telemetry systems for remote monitoring of wells in which transmission links send well data to a remote monitoring system.